SPM leonova emerald, User Manual

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C:10
Measurement techniques always included
B C
Vibration severity measurement
Vibration severity measurement according to ISO 2372 is a broad band measurement over the
frequency range 10 to 1000 Hz. It returns the RMS value of vibration velocity in mm/s (or inch/s).
This value is representative of the energy contents of machine vibration, and thus of the destructive
forces acting on the machine. It is still widely regarded as a good and easy to obtain indicator of
general machine condition.
Evaluation of machine condition
The evaluation consists of a comparison
of the measured value with the ISO limit
values recommended for 6 different
classes (see definition on the next page).
The majority of industrial machinery
belongs to the vibration classes 2, 3,
and 4:
Class 2: Medium size machines without
special foundations
Class 3: Large machines on rigid foun -
dations
Class 4: Large machines on soft foun -
dations.
For example, most smaller process pumps in a chemical plant would be Class 2. A 100 kW fan on a
concrete foundation would be Class 3. However, the same fan fastened to the less rigid metal deck
of a ship could be considered as Class 4.
Class 1 refers to independent parts of machines, for example electric motors up to 15 kW. Classes
5 and 6 are used for heavy reciprocating prime movers and machines which are intended to vibrate,
such as vibrating screens.
Leonova is programmed with the ISO limit values and will evaluate the measuring result, provided
the ISO machine class number is input under ‘Measuring point data’. On the instrument, the ISO
values for good and acceptable are shown as green. Just tolerable is yellow, unacceptable is red.